Abstract: A continuous ribbon resistor element having a plurality of conjunctive lengths alternately connected by reflexes is supported in a frame comprised of silicon bonded laminated mica. The ribbon elements are formed with a single, flat convolution center offset to one side of an original plane and lateral portions offset to an opposite side of the plane, joined to the center offset by transition portions such that the centroid for any transverse cross section lies on the original plane. The offsets originate at flat end portions near the reflexes and have maximum offset intermediate the ends. Metal members are received in openings of the laminated mica insulators to receive threaded fasteners when attaching an insulator in edge-wise relationship to another. Thermally conductive termination connections are brought outside the frame and airflow passageway to remove from the passageway the additional heat otherwise absorbed by the terminals.

Abstract: A method for remotely controlling flow of gaseous fuel to a burner having an electrically operated electromagnetically actuated modulating valve. The electromagnetic actuator comprises a coil having about one thousand turns of fine wire disposed proximate an annular permanent magnet. Either the magnet or coil may be attached to a moveable valve member which has a resilient poppet biased to close on a valve seat to shut off gas flow. Upon energization of the coil, a magnetomotive force is generated and moves the poppet off the seat to permit flow. Increased current flow in the coil proportionately increases opening of the poppet and movement of a metering member which throttles flow. When the poppet is fully open, flow is reduced to minimum metered level. A single user operated, remotely located potentiometer can be used to effect the proportional control of flow to the burner. In the preferred embodiment the metering member is cylindrical with a varying area grove or recess.

Abstract: In a bistable shape memory effect, SME, mechanism having first and second opposing shape memory effect, SME, elements (16, 20) moving an actuator (12) along a travel stroke between respective first and second positions upon heating of the respective SME element above its transition temperature mechanical frictional retainers are provided for holding the actuator at the end of its travel stroke, including after cooling of the respective SME element and return repose movement thereof. One embodiment provides a detent retainer (38, 40, 42, 44, 46). Another embodiment provides a friction wedge retainer (12a, 12b, 14a, 14b, 12c, 12d, 14c, 14d). Another embodiment provides a resiliently biased friction member (50, 52) and a lost motion coupling (56, 58) between the actuator and the SME elements.